A rendering of the DeltaWing GT racer. Two- and four-door street-legal models would maintain the same basic dart-shaped layout.

Suspension problems may have soured things at Sebring over the weekend, but the folks behind the DeltaWing program are anything but downbeat these days.

Quite the contrary. They’re confidently planning to move ahead with efforts to build not just one but a family of street legal cars based on the radical DeltaWing design. First seen on track during the 2012 running of the Le Mans endurance race, the DeltaWing is a dart-shaped race car that focuses on light weight and advanced aerodynamics rather than massive amounts of horsepower.

Backed by Don Panoz, the Georgia-based entrepreneur and race team owner, DeltaWing Technology Group says preliminary testing shows it could deliver sporty performance – and more than 70 miles per gallon. If that held up with a production model, it rival the best of today’s hybrids and even more advanced plug-in hybrid vehicles.

“This is an important point in the DeltaWing project’s next phase,” said the 80-year-old Panoz, who serves as the company’s chairman and CEO. “We’ve been very busy leading up to this launch announcement and we’ll remain quite busy coordinating the race car project’s many details.”

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DeltaWing has been tweaking its track design extensively since the first version made its debut at Le Mans. The team took a fourth-place finish in the Petit Le Mans last year and had high hopes going into this year’s season-launching 12 Hours of Sebring. But suspension issues left it sitting in pit row at the end of the race.

The latest DeltaWing race car shown during its abortive run at last weekend's 12 Hours of Sebring.

The race car is about as radical a shift as anything that’s been on track in recent decades, and is instantly recognizable with its narrow nose and relatively tiny front tires, the body flaring back into a dart-like shape. The idea is to significantly reduce weight and improve aerodynamics so the DeltaWing can keep up with its rivals using barely half the horsepower and a lot less fuel.

That basic concept carries over to the production models that the company envisions. Along with a DeltaWing GT race car, the company is working on street-legal models in both two and four-seat configurations, Panoz announced.

As with the race car, the road cars would use the basic dart-shaped layout, with their engines in the rear. The layout, the company claims, “allows engineers to use much smaller steering, braking, suspension, and other components up front to reduce overall mass and weight. Less mass and weight means less horsepower is needed to propel the vehicle, which in turn decreases fuel consumption and greenhouse gas emissions.”

Under new engineering chief – and racing veteran – Brian Willis, the focus is on powering the street model with a 1.4-liter, 138-horsepower four-cylinder gas engine. A preliminary analysis done by Meszler Engineering Services indicated an unadjusted EPA fuel economy rating of about 74 mpg Highway and 57 mpg in the Combined city/highway test.

That would put it well above the 54.5 mph target the EPA has set for the U.S. market in 2025 and would conceivably make it the most fuel-efficient gasoline vehicle on the road today. Only the three-wheeled Elio – which uses an equally radical shape and just three wheels – is targeting higher numbers.

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It’s possible the DeltaWing could also go with even more efficient hybrid or pure electric powertrain options.

“I’m very pleased to see how this objective testing validates and even exceeds our initial estimates,” said Panoz.

DeltaWing is estimating it would cost about $60,000 for its two-seat, high-performance track model, the 350-horsepower GT. But it wants to bring the driveway-ready four-seater in for something closer to $30,000. While the company says it is moving ahead rapidly on the project it hasn’t set a timetable for getting the DeltaWing on the road. Among other things, it still has to decide whether it will build the car itself or try to find a partner.

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